Truck Repair: 1989 chevy 4x4 wont start, oil pressure switch, chevy 4x4

Question
I just picked up a 1989 chevy 4x4 5.7 liter that has been sitting and rotting for some time.  Yesterday I installed new "y" pipe and muffler so I can drive it to the exhaust shop and have rest replaced. anyways truck turned over for a while before starting rather warm or cold so I replaced plugs wires dist. cap and rotor Truck still turned over for a long time before starting. eventually I killed the battery, replaced it and it wont even try to start. I have moved the dist. back and forth a bit to try to help cuz I knew the guy that had it before me messed with it.  Sure it may be flooded but still just turns over.  Please help thanx!

Answer
First, can you hear the fuel pump run when you turn the key to run? Should run for two seconds.
As a backup, there is an oil pressure switch that runs the fuel pump directly, once oil pressure builds to over 4 PSI.
Your cranking symptom sounds like the relay isn't working, and it is depending on the oil pressure switch.

Check the fuel pump fuse, relay, and wires.

Van